The present invention relates to an ink jet head, an ink jet head cartridge and an ink jet device usable as a printer, a video printer or the like as an output terminal for a copying machine, a facsimile machine, a word processor, a host computer, a video printer or the like. In this specification, recording includes application of ink onto any ink supporting material for receiving the ink, such as textile, thread, paper, sheet material (print), and what is recorded includes meaningful image such as letter or the like and meaningless image such as pattern images. The recording device includes various information processing device or a printer as an output device therefor, and the present invention is applicable to all of them.
An ink jet recording device which ejects ink onto a recording material to effect the recording has been put into practice, and may of them are produced, since it is advantageous in the easiness of downsizing, low noise or the like.
Recently, further downsizing or further improvement of the image quality particularly in color image recording, is demanded. In order to meet the demand, Japanese Laid Open Patent Application No. SHO-55-132259 has proposed a construction wherein a plurality of electrical heat exchange elements are provided in one nozzle. These electrothermal transducer elements are independently controlled and driven, so that size of the ink droplet ejected is controlled to accomplish high image quality recording (tone gradient recording method).
The investigations of the inventors in this respect have revealed the following.
An area of electrothermal transducer element is normally one of an important factors of determination of ejection amount of the ink. However, the maximum ejection amount of the ink when the plurality of the electrothermal transducer elements are used, is not determined by the total of the areas of the plurality of electrothermal transducer elements.
Since the heat produced by an electrothermal transducer element is influential to another electrothermal transducer. Therefore, the desired ink ejection amount is not accomplished easily.
The circuit construction on an element substrate (heater board) for driving the electrothermal transducer element in an example, is as shown in FIG. 22 or FIG. 23.
In FIG. 22, the electric signal is directly supplied to the electrothermal transducer element 012 through wiring and outside end portion 015 (direct wiring construction).
With such a circuit construction, the construction in the element substrate is simple, but as to the number of the contacts, when the number of the electrothermal transducer elements is n, at least n+ one contacts are necessary. When a plurality of electrothermal transducer elements are provided in a single nozzle with such a circuit construction used, a very many electrical connections are necessary between the element substrate and the outside devices, with the result of complication of the-manufacturing step and bulkiness of the element substrate.
The element substrate of FIG. 23 has electrothermal transducer element 012, wiring 013, diode 014 and contact for external connection. When electric energy supply is effected by the matrix construction constituted by wiring and diode. By the use of the diode matrix construction, the number of of the contacts 015 for the external connection is reduced to 2n when the number of of the electrothermal transducer elements is n.
Even if, however, such a wiring construction is used, the number of of the connection contacts is quite large in the case of tone gradient recording head.
As described above, the head having a plurality of of heat generating resistors in 1 nozzle, involves the problem of lowering of the ejection efficiency or deviation from a desired ejection amount.
Accordingly, it is a principal object of the present invention to provide an ink jet head, a head cartridge, and an ink jet recording device capable of effecting high image quality recording with high tone gradient and improved ejection efficiency.
It is another object of the present invention to provide an ink jet head, ink jet head cartridge and ink jet device wherein increase of the number of of electrical contacts on an element substrate resulting from a plurality of electrothermal transducer elements in a single nozzle and the resultant bulkiness of the substrate, can be prevented.
It is a further object of the present invention to provide a container for ink containing ink properly refilled thereinto, usable in an ink jet head or an ink jet head cartridge according to the present invention.
According to the present invention, the position of a plurality of heat generating resistors are optimization in a single nozzle (flow path).
According to the present invention, the function elements for driving the heat generating resistors in such a head are built in the same element substrate, by which the number of of the electrical contacts for the external connections can be decreased, and the downsizing of the element substrate is accomplished. As an ink container for constituting such an ink jet head or ink jet cartridge, an ink container to which the ink is refilled is used, so that the repeated use is permitted, so that the ink jet cartridge can be used for a long term.
According to an aspect of the present invention, there is provided An ink jet head comprising a plurality of liquid flow paths for ejecting the ink; and a plurality of heat generating resistors for said respective liquid flow paths, said heat generating resistor being independently drivable; wherein adjacent ones of said heat generating resistors are spaced by not more than 8 microns.
According to another aspect of the present invention, there is provided an ink jet head cartridge having a maintaining for containing the ink to above-described ink jet head or the ink jet head.
According to a further aspect of the present invention, there is provided an ink jet device having the ink jet head and transporting means for transporting a recording material.
According to a further aspect of the present invention, there is provided an ink jet device having a driving signal supply means for driving such an ink jet head or said ink jet head.
According to a further aspect of the present invention, there is provided a refilled ink container for above-described ink jet head cartridge.
While the invention has been described with reference to the structures disclosed herein, it is not confined to the details set forth and this application is intended to cover such modifications or changes as may come within the purposes of the improvements or the scope of the following claims.